Turntable carried communicating motor and switch mounting chamber



Sept. 7, 1954 c. P. BALDWIN TURNTABLE CARRIED COMMUNICATING MOTOR AND SWITCH MOUNTING CHAMBER Ongmal Flled Dec 20, 1946 INVENTOR: CLYDE P BALDWIN ATTORNEY Patented Sept. 7, 1954 UNITED STATES ATENT OFFICE TURNTABLE CARRIED COMMUNICATING BIOTOR AND SWITCH MOUNTING CHAM- BER Clyde P. Baldwin, Claremont, N. IL, assignor to Joy Manufacturing Company, a corporation of Pennsylvania 2 Claims. 1

This invention relates to coal mining apparatus and more particularly to a coal mining machine having an improved supporting structure for the kerf cutting mechanism and its electric driving motor together with improved motor control means.

A coal mining machine such as is used in underground coal mines must be vertically compact and rugged in design and all electrical connections and electrical control apparatus should be of an explosion-proof construction. The present invention contemplates improvements over known types of coal mining machines in that the electric driving motor for the kerf cutting mechanism has its casing formed integral with the turntable frame on which the kerf cutting mechanism is mounted, and the control switch for the driving motor is arranged in an explosion-proof chamber formed within the integral motor casing and turntable frame. By forming the motor casing integral with the turntable frame it is also possible to attain extreme vertical compactness which is of substantial importance in a low height machine designed for use in mines having low head-room.

An object of the present invention is to provide an improved coal mining apparatus whereby, due to its novel design, extreme vertical com- .pactness is attained. Another object is to provide an improved turntable and motor construetion which lends itself to low height. A further object is to provide an electrically driven mining machine wherein the casing of the electric driving motor for the kerf cutting mechanism is made integral with the turntable frame and co operates with the latter to provide an explosionproof chamber in which the motor control switch is enclosed, thereby to reduce the possibility of an explosion in a gaseous mine. These and other objects and advantages of the invention will, however, hereinafter more fully appear in the course of the ensuing description and as particularly pointed out in the appended claims.

This application is a division of my copending application Serial No. 717,398 filed December 20, 1946.

In the accompanying drawing there is shown for purposes of illustration one form which the invention may assume in practice.

In this drawing:

Fig. l is a plan view of a coal mining apparatus in which a preferred illustrative embodiment of the invention is incorporated.

Fig. 2 is an enlarged longitudinal Vertical sec- 2 tional view taken in the planes of line 2--2 of Fig. 1.

The coal mining apparatus with which the present invention is associated is of the horizontal kerf cutting, mounted track cutter type supported and guided by a mine trackway, although it will be evident that various features of the invention may be incorporated in mining apparatus of various other types.

The coal mining apparatus disclosed herein generally comprises a self-propelled truck I mounted on wheels 2" adapted to travel along a trackway 3 laid on the mine floor. Supported on the truck midway between the sides thereof and longitudinally between the front and rear wheel axes is a horizontal turntable 4', in turn supporting an elongated swingable' arm structure or boom 5, overhanging the forward end of the truck and which carries at its outer extremity a horizontal kerf cutter 6'. Supported on the turntable is a horizontal electric motor l for driving the kerf cutter, and supported on the rearward portion of the truck rearwardly of the turntable is a horizontal electric motor 8 for driving pumping means 9 which provides a source of fluid under pressure for a truck wheel driving motor Ill and the various other fluid operated devices of the apparatus. Arranged on the truck frame longitudinally between the turntable and the motor 8 is a control valve mechanism l i for controlling fluid flow relative to the various fluid operated devices and to the motor 50, while located at the rear end of the truck rearwardly of the motor 8 is a reelingmechanism 12 for the electric power conductor for supplying electric power to the motors land 8.

The truck i comprises a truck frame M oian extremely low compact design and the turntable is mounted in a relatively low position between the truck wheels and has a depending circular bearing support i5 journ'aled for rotation about a vertical axis within bearing. sleeves It supported by a circular' bearing support ['1 integral with the truck frame. A circular bearing portion iii of the turntable extends downwardly and has attached thereto, as by screws, a bottom plate it which engages the lower bearing sleeve for retaining the turntable in position in its bearing mounting on the truck frame. The electric motor I is preferably arranged horizontally in a relatively low position at the top of the turntable with the axis of the motor power shaft i9 horizontally disposed. This motor herein preferably has its rear end located rearwardly of the turntable axis with its forward portion projecting horizon- 3 tally in advance of the turntable, and has its casing preferably formed integral with the turntable frame, as shown in Fig. 2. A front motor head or rigid front support 2| is secured to the forward end of the motor casing 20 and carries a circular bearing support 22 coaxial with the motor power shaft and supports a bearing 23 in which the forward portion of the motor shaft is journaled, and the rear wall 24 of the motor casing supports a bearing 25 for the rearward portion of the motor shaft. The adjustable arm structure or boom 5 of the kerf cutter is mounted on the front support 2| in the manner fully disclosed in the copending application Serial No. 717,398 referred to above.

The means for rotating the turntable 4 about its axis to swing the cutter supporting arm structure horizontally relative to the truck comprises fluid cylinders 21 pivotally mounted at 28 on brackets 29 secured to the sides of the rigid front support 2|, and reciprocable pistons contained in these cylinders have rearwardly projecting piston rods 30 which are pivotally connected at 3| to brackets 32 secured to the sides of the truck frame. Thus, the cylinders and piston rods may swing in horizontal planes and when fluid is properly supplied to the cylinders, the turntable, the motor casing, the arm structure 5 and the ken. cutter 6 may be swung in horizontmtplanes relative to the truck, and when trapped in the cylinders 21, the turntable and the structure supported thereby may be locked against swinging movement with respect to the truck frame.

The cutter chain driving motor 1 is herein a reversible motor and may be reversed so that the kerf cutter may be driven in either of opposite directions, and to effect motor reversal, a manually operable reverse switch 35 of a conventional design is arranged in an improved manner within a chamber 36 within the depending bearing portion I5 of the turntable 4, as shown in Fig. 2. The usual wires lead from the cable reel mechanism l2 to this switch and wires 31 lead from this reverse switch and are connected in the motor circuit so that when the switch is moved to reverse position, motor reversal is efiected. The chamber 36 communicates through an opening 38 in the bottom wall 39 of the motor casing with the motor casing chamber 40, and the chamber 36 is totally enclosed and explosion-proof. By forming the motor casing integral with the turntable frame the need for sealing joints between the casing and frame is eliminated and the motor casing is located in a relatively low position close to the top of the turntable.

As a result of this invention an improved coal mining apparatus of the low-vein, mounted type is provided by forming the motor casing integral with the turntable frame extreme low height is attained and by forming a chamber within the turntable and the elimination of all joints between the motor casing and the turntable frame,

an explosion-proof enclosure for the motor reverse switch is provided. Further, by arranging the motor control switch within an explosionproof chamber within the turntable frame, a more convenient switch location is provided. Other advantages of the invention will be clearly apparent to those skilled in the art.

While there is in this application specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In an apparatus of the character disclosed, the combination comprising a support, a turntable journaled on said support and having a frame provided with a circular portion, a reversible electric motor having its casing secured to said turntable frame and provided with a chamber, said motor having a conventional motor circuit, said circular portion of said turntable frame providing a closed explosion proof chamber having communication with said chamber of said motor casing, a reverse switch enclosed in said chamber in said circular portion, wiring extending from said switch through said cham ber in said circular portion into said motor casing chamber and connected into the motor circuit, and a switch control member connected to said switch and located on said turntable frame exteriorly of said chamber.

2. In an apparatus of the character disclosed, the combination comprising a support having a circular recess, a turntable mounted on said support to turn relative thereto on a vertical axis, said turntable having a frame provided with a circular bearing portion projecting into said circular recess, an electric motor on said turntable and having its casing secured to said turntable frame and at least in part overlying said recess, said bearing portion having a closed explosion proof chamber therein, a motor control switch arranged in said chamber, said chamber providing an explosion proof enclosure for said switch, and an operating means for said switch located on said turntable frame exteriorly of said chamber.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,734,940 Cartlidge Nov. 5, 1929 1,881,744 Lindgren Oct. 11, 1932 2,269,781 Osgood Jan. 13, 1942 FOREIGN PATENTS Number Country Date 642,514 Germany Mar. 6, 1937 

